In an electrophotographic imaging process used in printers, copiers and the like, a photosensitive member, such as a photoconductive drum or belt, is uniformly charged over an outer surface. An electrostatic latent image is formed by selectively exposing the uniformly charged surface of the photosensitive member. Toner particles are applied to the electrostatic latent image, and thereafter the toner image is transferred to a media sheet intended to receive the final image. The toner image is fixed to the media sheet by the application of heat and pressure in a fuser assembly. The fuser assembly may include a hot roll and a backup roll forming a fuser nip through which the media sheet passes. Alternatively, the fuser assembly may include a fuser belt, a heater disposed within the belt around which the belt rotates, and an opposing backup member, such as a backup roll. The backup roll, for either fuser belt or hot roll architectures, is typically driven and includes a shaft and gear coupled thereto. The backup roll gear engages with a drive gear located in the printer for receiving power from a motor, such as a brushless DC motor, disposed within the printer. Activating the motor causes the drive gear in the printer and the backup roll gear in the fuser assembly to rotate, which rotates the backup roll in the fuser assembly so as to pass a sheet of media through the nip of the fuser assembly for fusing recently transferred toner to the media sheet.
The brushless DC motor typically includes or is otherwise associated with a sensing arrangement coupled to the controller of the imaging device. The sensing arrangement senses motor position generated by Hall Effect sensors responsive to the motor magnets and provides the sensed motor position to the controller. The controller then performs motor commutation using the sensed motor position.
During fuser installation, it may not always be clear for new and even experienced users to know whether or not the fuser assembly is properly installed. Thus, a need exists to know when the fuser assembly is fully inserted to its operable position within the imaging device.